1. Field
Embodiments of the present disclosure relate to an ultrasonic diagnostic apparatus in which steps are formed at edge portions of a piezoelectric layer to maintain the performance of the ultrasonic diagnosis apparatus while stabilizing the process of the ultrasonic diagnosis apparatus to thereby improve yield, and a manufacturing method of the ultrasonic diagnostic apparatus.
2. Description of the Related Art
An ultrasonic diagnostic apparatus irradiates ultrasonic signals to a target region of an object from the surface of the object, and receives ultrasonic signals (ultrasonic echo signals) reflected from the target region so as to non-invasively acquire section images about soft tissue of the object or images about blood vessels of the object based on information of the echo ultrasonic signals. The ultrasonic diagnostic apparatus has advantages that it is a compact, low-priced apparatus and it can display images in real time, compared to other medical imaging apparatuses, such as an X-ray diagnostic apparatus, an X-ray Computerized Tomography (CT) scanner, a Magnetic Resonance Image (MRI) apparatus, and a nuclear medical diagnostic apparatus. Also, the ultrasonic diagnostic apparatus has high safety since there is no risk for patients to be exposed to radiation such as X-rays. For the advantages, the ultrasonic diagnostic apparatus is widely used to diagnose the heart, abdomen, urinary organs, uterus, etc.
The ultrasonic diagnostic apparatus includes a transducer to transmit ultrasonic signals to an object and to receive ultrasonic echo signals reflected from the object, in order to acquire an ultrasonic image of the object.
The transducer may include a piezoelectric layer to convert electrical signals into acoustic signals or acoustic signals into electrical signals according to vibration of a piezoelectric material, a matching layer to reduce a difference in acoustic impedance between the piezoelectric layer and an object so that a major part of ultrasonic waves generated from the piezoelectric layer can be transferred to the object, a lens layer to focus ultrasonic waves moving forward from the piezoelectric layer on a specific region, and a backing layer to block ultrasonic waves from being transmitted backward from the piezoelectric layer to prevent image distortion.